Arc-light electrode.



J. HKRDEN.

ARO LIGHT ELECTRODE. A PPLIGATION FILED DEO.10, 190a.

Inventor: Johannes Hrde'n,

UNITED STATES PATENT OFFICE.

JOHANNES HARDEN, F SCHENECTADY, NEWYORK, ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ARC-Liam ELECTRODE.

Specification of Letters Patent.

Patented Mar. 5, 1912.

' Application filednecember 10, 1903. Serial No. 184,565.

To all whom "it may concern:

' Be it known that I; JOI-IANNES HA'RmiN, a subject of they King of Sweden and Norway, residing at Schenectady, .in the county of Schenectady 'and State of New York, have invented certain new and useful Improvements in Arc-Light Electrodes, of which the following is aspecification.

The object of my present invention is the provision of an are light electrode which gives an etfieient luminous or flaming arc and which possesses other features fitting it for use in an arc lamp.

I have found that an electrode containing more or less form-manganese, which may bid, 40 parts of form-manganese and parts of carbon. which is moistened with a suitable binder (which may (JOIISlSt of water and oil), to render it plastic, gives satis factory results. From the plastic mass thus formed electrodes may be molded into the form of pencils or the like. after-which they are baked for some time at a fremperature of from 200 to 300 u, to remoye the moisture contained in them. After removing the moisture from the electrodes, they arefired some time at a temperature of from 1200 to. 1300 C. The electrodes thusformed give good flaming or luminous arcs having a slightly bluish tinge, are but slowly consumed in the normal operation of the lamps, in which they may be employed, and do not formslags at their tips which are nonconducting when cold. Such electrodes work more satisfactorily in direct than in alternating current circuits. They can, however, be employed in either kind of circuit.

It will, ofcourse, be understood that the method'above specified is butone of many in which electrodes containing ,ferro-manganese may be formed.

In the ferro-manganese which I employ in the manufacture of are light electrodes the'iron and manganese may be combined in proportions varying from 60 parts of iron and 40 parts of manganese to 90 parts of iron and 10-parts of manganese. I prefer, however, to employ form-manganese com- .posed of from 30 to 40 parts of manganese and from 70 to 60 parts of iron.

What I claim-as new and desire to' secure by Letters Patent of the 'UnitedStates, is,

1. An arc light electrode containing titanium carbid, form-manganese, and carbon. 2. An are light electrode, containing two parts of titanium earhid, two parts of erromanganese, and one part of carbon.

3. An are light electrode, consisting, of forty per cent. of titanium carbid, forty per cent, of form-manganese, and twenty per cent. of carbon.

-In witness whereof, I have hereunto set my hand this third day of December, 1903..

JOHANNES HARDEN.

Vitnesses:

BENJAMIN B. HULL, HELEN Queen. 

